Asymmetric gait is sometimes developed in individuals with central nervous system damage, such as stroke, or in persons who have suffered damage to the spinal cord, brainstem, cerebellum, or motor cortex. In such cases, a limp is developed and the person does not fully extend his foot far enough backward, which can prevent him from effectively pushing off into the swing phase of his gait.
In such cases, rehabilitation is often provided using a split-belt treadmill having two independent belts that can be operated at different speeds to exaggerate the asymmetry of the person's gait. In particular, the belt associated with the weak leg can be driven faster than the belt associated with the strong leg. An adaptation process occurs during such rehabilitation such that, once the belts are operated at the same speed, an altered walking pattern is retained as an after-effect.
Continuous and repeated split-belt gait training has been found to temporarily restore a normal walking pattern. However, individuals with such corrected walking patterns typically only retain them for a short period of time and the gait pattern often does not transfer to walking over a normal walking surface, such as the floor or ground. Because the adaptation effects only last for a short period of time, the effects of long-term training are still unknown.
In view of the above discussion, it can be appreciated that it would be desirable to have a way to provide rehabilitation to persons with asymmetric gait other than using split-belt treadmill therapy.